Christian beliefs: God, Trinity, incarnation, salvation and eschatology
What this domain tests
This section tests core Christian doctrine: God, the Trinity, incarnation, salvation and the last things. You need precise definitions and the ability to distinguish orthodox teaching from common simplifications.
Core rules and concepts
- Trinity: one God in three Persons, Father, Son and Holy Spirit, sharing one divine essence (ousia). The Persons are distinct relations, not three gods and not three masks.
- Nicaea (325) condemned Arius and confessed the Son as homoousios, of the same being as the Father. Constantinople (381) affirmed the Spirit's divinity. Chalcedon (451) defined the incarnate Christ as one person in two natures.
- Salvation: the work of Christ saves through his life, death and resurrection. Classic models include Christus Victor, satisfaction, moral influence and sacrificial/ransom imagery; Catholic theology holds them together rather than choosing one exclusively.
- Eschatology: Christ's return, resurrection of the body, particular and final judgment, heaven and hell; Catholic teaching also includes purgatory as purification for the saved.
Worked example
Why does the Church insist on homoousios rather than homoiousios ('similar being')? Reasoning: if the Son is only similar to the Father, then God is not fully revealed in Christ and salvation is uncertain. Homoousios safeguards the claim that the one who saves is truly God. It is a doctrinal boundary, not a philosophical ornament.
Traps
Modalism (one Person in three modes); Arianism (Son as creature); partialism (three parts of God); confusing justification with sanctification; treating purgatory as a second chance.